Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people, just like you, are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
Solved

Using the generic type 'System.Collections.Generic.List<T>' requires '1' type arguments

Posted on 2009-04-06
7
5,630 Views
Last Modified: 2013-12-17
I have used code to merge cells in gridview but it shows error


 Using the generic type 'System.Collections.Generic.List<T>' requires '1' type arguments


so can you help your suggest anything for the same???????
public static List<T> MakeList_tmp<T>(T temp)
        {
            List<T> newList = new List<T>();
            return newList;
        }
 
 
 
        private void mergeRows(GridView gv)
        {
            string lastColumn1 = string.Empty;
            
            GridViewRow currentRow = null;
            GridViewRow tmp = null;
            var temp = tmp;
            var tempRow = MakeList_tmp(temp);
            System.Collections.Generic.List tempRows = new System.Collections.Generic.List();
            
            foreach (GridViewRow row in gv.Rows)
            {
                if (row.RowType == DataControlRowType.DataRow)
                {
                    string currentColumn1 = string.Empty;
                    currentColumn1 = Convert.ToString(row.Cells[0].Text);
 
                    if (currentRow == null)
                    {
 
                        currentRow = row;
                        lastColumn1 = Convert.ToString(row.Cells[0].Text);
 
                    }
 
 
                    else
                    {
                        if (lastColumn1 != currentColumn1)
                        {
 
                            currentRow.Cells[0].RowSpan = tempRows.Count + 1;
                            currentRow.Cells[0].VerticalAlign = VerticalAlign.Middle;
                            currentRow.Cells[0].HorizontalAlign = HorizontalAlign.Center;
 
                            foreach (GridViewRow row1 in tempRows)
 
                                row1.Cells.RemoveAt(1);
                            lastColumn1 = currentColumn1;
 
                            tempRows.Clear();
                            currentRow = row;
                            lastColumn1 = currentColumn1;
                        }
                        else
                        {
 
                            tempRows.Add(row);
                        }
                    }
                }
            }
           
            if (tempRows.Count >= 0)
            {
                
                currentRow.Cells[0].RowSpan = tempRows.Count + 1;
                currentRow.Cells[0].VerticalAlign = VerticalAlign.Middle;
                currentRow.Cells[0].HorizontalAlign = HorizontalAlign.Center;
 
                foreach (GridViewRow row1 in tempRows)
                    row1.Cells.RemoveAt(0);
            }
        }
protected void GridView1_PreRender(object sender, EventArgs e)
        {
            GridView gv1 = (GridView)sender;
            mergeRows(gv1);
 
        }

Open in new window

0
Comment
Question by:scspl
  • 4
  • 3
7 Comments
 
LVL 143

Accepted Solution

by:
Guy Hengel [angelIII / a3] earned 500 total points
ID: 24074963
what about this:
public static List<T> MakeList_tmp<T>()   // if you need and argument, it shall by <T> temp and not T temp, AFAIK
        {
            List<T> newList = new List<T>();
            return newList;
        }
 
and later: 

     private void mergeRows(GridView gv)
        {
            string lastColumn1 = string.Empty;
            
            GridViewRow currentRow = null;
            GridViewRow tmp = null;
            List<GridViewRow> tempRows = MakeList_tmp();
            ...

Open in new window

0
 

Author Comment

by:scspl
ID: 24074994
So, if here

GridViewRow tmp = null;

List<GridViewRow> tempRows = MakeList_tmp();


i want to pass tmp with MakeList_tmp(tmp) so

how it should be written over here and how the argument will be passed to

the MakeList_temp() <----    function....
0
 
LVL 143

Assisted Solution

by:Guy Hengel [angelIII / a3]
Guy Hengel [angelIII / a3] earned 500 total points
ID: 24075019
as I explained in the comment of the previous comment:
public static List<T> MakeList_tmp<T>(<T> tmp)  

Open in new window

0
Master Your Team's Linux and Cloud Stack!

The average business loses $13.5M per year to ineffective training (per 1,000 employees). Keep ahead of the competition and combine in-person quality with online cost and flexibility by training with Linux Academy.

 

Author Comment

by:scspl
ID: 24075094
it is not accepting that...

<T> tmp -->  is not a valid argument.....

so is there any other way...
public static List<T> MakeList_tmp<T>(<T> tmp)   
{
    List<T> newList = new List<T>();
    return newList;
}
 
 
 
 
// Above code generates the error:->
 
// Compiler Error Message: CS1031: Type expected

Open in new window

0
 
LVL 143

Expert Comment

by:Guy Hengel [angelIII / a3]
ID: 24075111
sorry, in the method parameter data type, it's without the <>
public static List<T> MakeList_tmp<T>(T tmp)   
{
    List<T> newList = new List<T>();
    return newList;
}
 

Open in new window

0
 

Author Comment

by:scspl
ID: 24075126
That matter is solved but tell me one thing

where will  the method  mergeRows() called?

will it be before databinding or after that???
0
 

Author Comment

by:scspl
ID: 24075141
now i got it it's working thanks a lot for your help


it will be called after binding the data to the data grid

other wise it will show the null reference error.

because it will not have any data into cells without binding..



thank you

again angel
0

Featured Post

Master Your Team's Linux and Cloud Stack

Come see why top tech companies like Mailchimp and Media Temple use Linux Academy to build their employee training programs.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Many of us here at EE write code. Many of us write exceptional code; just as many of us write exception-prone code. As we all should know, exceptions are a mechanism for handling errors which are typically out of our control. From database errors, t…
Real-time is more about the business, not the technology. In day-to-day life, to make real-time decisions like buying or investing, business needs the latest information(e.g. Gold Rate/Stock Rate). Unlike traditional days, you need not wait for a fe…
Microsoft Active Directory, the widely used IT infrastructure, is known for its high risk of credential theft. The best way to test your Active Directory’s vulnerabilities to pass-the-ticket, pass-the-hash, privilege escalation, and malware attacks …

838 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question